Apparatus and method for burnishing metal objects

ABSTRACT

A vibratory burnishing machine includes a drum which is supported on a table for vibratory movement. A frame on the drum includes a rotating counterweight which during rotation imparts vibratory movement to the drum. The vibratory movement is imparted to burnishing media in the form of steel balls or shot which burnish metal articles within the drum. The machine is particularly adapted for polishing small articles of flat and circular configuration such as coins by the combination of an open end cylinder which is freely moveable in the drum in response to movement of the burnishing media.

United States Patent Shiplov 51 Aug. 1, 1972 [54] APPARATUS AND METHODFOR BURNISHING METAL OBJECTS [72] Inventor: George J. Shiplov, VillaPark, Ill.

[73] Assignee: Twin-Orb Corporation [22] Filed: Feb. 16, 1971 [21] App].No.: 115,615

[52] US. Cl. ..51/163, 259/72, 51/313 [51] Int. Cl. ..B24b 31/00 [58]Field of Search ..259/72, DIG. 42; 51/7, 163,

[56] References Cited UNITED STATES PATENTS 2,174,879 10/1939 Hilbishetal ..51/164 Primary Examiner-Francis S. Hosar Attorney-Hilmond O.Vogel [5 7] ABSTRACT A vibratory burnishing machine includes a drumwhich is supported on a table for vibratory movement. A frame on thedrum includes a rotating counterweight which during rotation impartsvibratory movement to the drum. The vibratory movement is imparted toburnishing media in the form of steel balls or shot which burnish metalarticles within the drum. The machine is particularly adapted forpolishing small articles of flat and circular configuration such ascoins by the combination of an open end cylinder which is freelymoveable in the drum in response to movement of the burnishing media.

18 Claims, 4 Drawing Figures msmsnm 1 m v 3.680.266

SHEET 1 BF 2 INVENTOR.

GEORGE J. SHIPLCV F|G 2 I v ATTORNEY PATENTEDAuc" 1 I972 SHEEI 2 [IF 2INVENTOP. GEORGE J. SHIPLOV wflfl ATTORNEY APPARATUS AND METHOD FORBURNISHING METAL OBJECTS BACKGROUND OF THE INVENTION 1. Field ofInvention This invention relates to the art of burnishing or SUMMARY OFTHE INVENTION It is a prime object of the present invention to providean improvement to a conventional burnishing or polishing machine whichpermits the utilization of the machine as an apparatus, and in a method,for polishing small flat cylindrical or circular metal articles such ascoins. The machine includes a conventional drum which is mounted forvibratory movementon a table. The drum has an arcuate bottom andcontains burnishing balls and a conventional comPound which may beliquid, is directed to and from the vessel in a re-circulatory cycle.Such a system is disclosed in the D. E. Roberts US. Patent No.3,353,796, patented Nov. 21, 1967. In the present invention acylindrical open end member is freely dispersed within the drum to movein response to vibration with the balls in a circulatory path whichadapts that machine for the efiicient and eflective burnishing ofrelatively small flat objects such as coins. Thus the machine isparticularly effective for coin polishing or the like.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross sectional view ofavibratory drum mounted on a table;

FIG. 2 is a cross sectional view taken particularly along the line of22ofFIG. 1;

FIG. 3 is a perspective view of an open end cylinder; and;

FIG. 4 is a cross sectional view of a modified drum arrangementincluding means for discharging burnishing balls from the drum.

DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 discloses a vibratorymachine generally designated at which includes a suitable table 11havwhich may be pumped therefrom in a circulatory system from an outletfitting 20.

The drum 13 has connected thereto a frame 21 comprising vertical plates22 which are interconnected at their lower portion by a suitable supportbracket 23. An electric motor 24 is mounted on the bracket 12 andincludes a drive pulley which by means of a belt 26 drives a drivenpulley 27 mounted on a shaft 28 which is suitably supported on theplates 22 for rotation. One or more counterweights 29 are connected tothe shaft 28 for rotation therewith and during rotation impart vibratorymovement to the drum 13. The motor need not necessarily be mounted onthe frame 21 but can be mounted on a suitable table frame (not shown).This type of machine is conventional as disclosed in the F errara US.Pat. No. 3,464,163 patented Sept. 2, 1969.

As best shown in FIG. 3, a cylinder 30 includes a plurality of openings31 and the cylinder 30 is open at opposite ends. The openings 31 may beof various sizes and shapes to freely permit the burnishing media in theform of steel balls 32 and the liquid compound to flow freelytherethrough during the burnishing operation. As indicated in theFigures, a charge of monetary coins 33 is placed in the drum 13 to besubjected to the burnishing or polishing operation.

In the modification shown in FIG. 4 the machine is identical to thatabove described. However in addition the drum 13 is provided with meanspermitting the burnishing balls 32 to be discharged from the drum andthereby the coins 33 are retained therein so that they can be easilyremoved. In this modification the drum 13 includes a plurality ofopenings 34 which extend throuGh the wall 14 and through the adjacentliner 16. The openings 34 are of a size so that the balls 32 can easilYpass therethrough but are small enough to prevent the smallest coinburnished from passing from the drum 13.

A cover 35 is hingedly connected as indicated at 36 to the wall 14 andthe same is shown in the open position. The cover 35 includes a suitablegasket 37 which is in the closed position, shown in broken linessealingly covers the openings 34. A latch element 38 may be rotated overthe cover 35 to tightly maintain the cover in its latched or closedposition. A chute 39 is placed in position between the plates 22 fordirecting the discharged balls 32 into a container 40 carried on asupport 41.

OPERATION In conventional fashion the rotation of the counterweight 29causes vibratory movement of the drum l3 and the balls 32 containedtherein. Simultaneously burnishing compound is recirculated from asuitable pump and reservoir not shown from the nozzle 19 through thedrain fitting 20. The counterweights 29 are so positioned to createwithin the drum an orbital flow of the media as indicated by the arrows.

The cylinder 30 is placed in the drum as shown in FIG. 2, with its axisextending normal to the side walls 15. A charge of coins 33 is nowplaced into the drum 13. During vibration the coins, balls, and cylindermove in a direction as indicated by the arrows in FIG. 1. This may bedescribed as an orbital or circular path flow, the parts within the drumarriving at the top on the left hand side and then flowing in an arcuatepath to the right downwardly to the bottom of the drum, then arcuatelyagain to the top. At the same time the flow of the balls imparts arOtating movement to the cylinder 30 about its own axis, and also in asmaller orbital movement to remain in a more submerged position relativeto. the balls and simultaneously dragging coins with the ballsdownwardly toward the bottom of the drum where the most effectiveburnishing action occurs.

The cylinder is preferrably of a suitable steel, though other metals ormaterials may be utilized. By dimensioning the cylinder endsapproximatelY relative to the side walls as shown, stability of the sameis maintained against substantial variation from the transverserotational axis diSclosed.

It has been determined that the efficiency of burnishing of the coins isgreatly increased, both from a quality and time standpoint, by theutilization of the freely dispersed or floating cylinder. Some of thecoins may pass thru the openings 31 and then transversely through thecylinder intermingled with the burnishing balls and thus are subjectedto a slide zone action. This action is created in tumbling machineswhich have also been utilized for the burnishing of materials. Thus thevibratory action of the balls is supplemented by a slide zone orbumbling action of the cylinder and greatly improved results areobtained. Thus the movement of the media is thru the openings 31 normalto the cylinder axis and then along said axis outwardly from theopposite open ends of the cylinder. The. apertures or openings 31 alsopermit the balls 33 to freely pass therethrough and yet are'small enoughto prevent the coins from passing. Further the cylinder prevents thecoins from adhering to each other which will occur without the cylinderand thus retard proper and effective burnishing. The cylinder duringrotation also is effective to prevent the balls and coins from beingthrown out of the drum during heavy loading of the drum. Thus more coinscan be effectively processed.

The process of burnishing thus includes the steps of vibrating the ballswithin the drum wherein the vibratory motion is imparted to the coinswhich flow in a circular, or orbital path with the balls and thecylinder. The cylinder during such vibration also is freely carried insaid circular, or orbital, path and rotates about its own axis, in itsown orbit, thereby imparting a sliding action, such as occasioned bytumbling, to the burnishing media and the coins carried therein.

The arrows in FIG. 1 describe the rotation of the mass of media,cylindrical members and the charge of materials. As indicated above, thesemi-cylindrical shape of the drum and the off-center positioning of thecounterweight causes this flow in what is termed as an orbit or orbitalmovement. This is conventional. However, in the present process aportion of the media is treated to a separate smaller diameter orbitwithin the freely rotating cylindrical member, which second orbit moveswith the cylinder in the firSt orbit. Media and a portion of the chargeis temporarily confined in this smaller orbit, subjected to theburnishing tumbling action, is discharged from the cylindrical memberand additional material as portions of the mass are then so treated.

The cylindrical member is also effective, by virtue of the apertures, oropenings 31, through which the balls pass to agitate the mass of mediaand thus increase the effectiviness of the operation without all of thecoins necessarily passing through the cylinder. As indicated in theoperation hereinabove the passage of the steel balls through thecylinder is believed to be the primary causative factor for the improvedoperation. External visual observation indicates a phenomena occurringwhich provides for the increased effectiveness of the I burnishingballs. The eccentric vibratory or oscillating of the drum causes theballs to move in an orbital flowing pattern and in a fluid like manner,the balls entering in the apertures of the cylinder and out from theopposite ends thereof. This creates a turbulence within the mass ofballs below the upper surface thereof with the ballsbeing moved by thedrum to vary the density of a plurality of the balls in various placesin the drum to create a multi-convectional flow of the burnishing.

balls. This results in increased contact of the balls with the coinsresulting in a greater polishing effect in a shorter time. Thisincreased polishing effect is present throughout the drum because thecylinder is carried in the orbital path in the drum and is in an orbitof its own, so that the balls are carried also in an orbital path aroundthe cylinder.

After a certain period of operation, the door 37,'in the modification ofFIG. 4, is opened. The recirculation of liquid compound has been stoppedand the vibration is continued until the majority of the balls have beendischarged through the openings 34 thru the chute 39 and the container40. The coins remain in the drum and these may now be gathered andremoved.

What is claimed is:

l. A vibratory burnishing apparatus including;

a work drum for containing burnishing media and a charge of metalmaterials to be burnished,

means mounting said drum for vibratory motion,

vibratory means for inducing vibratory motion to said drum, therebyimparting an orbital movement of the media and said charge,

the improvement comprising,

a cylindrical member positioned within said drum,

said member being positioned within said drum and said media and chargefor rotation about its own axis,

said cylinder including opening means whereby during vibration of saiddrum and rotation of said cylinder, in response to vibration of saidmedia, said opening means provides for the passage of said media to andfrom said cylindrical member.

2. The invention in accordance with claim 1,

said openings being dispersed at opposite ends of said cylindricalmember and said cylindrical member being positioned in said media forfree movement therein.

3. The invention in accordance with claim 2,

said media including burnishing balls,

4. The invention in accordance with claim 2,

said cylindrical member moving in its own orbit in response to saidorbital movement of said media.

5. The invention in accordance with claim 4,

said cylindrical member having a cylindrical wall provided with aplurality of apertures permitting the free flow of media therethrough.

6. The invention in accordance with claim 5,

said apertures being of a size smaller than the individual components ofsaid charge.

7. The invention in accordance with claim 1,

said drum having a semi-cylindrical bottom wall and vertical side wallsconnected thereto,

said cylindrical member being despersed with its axis normal to saidwalls and being freely moveable within said drum in response to movementof said media.

8. The invention in accordance with claim 7,

said opening means including openings dispersed at opposite ends of saidcylindrical member and said openings being in relatively close adjacentrelation to said vertical walls.

9. The invention in accordance with claim 7,

said cylindrical member including a cylindrical wall having a pluralityof apertures through which said burnishing media passes.

- 10. A method of burnishing metal articles of relatively small sizecomprising the steps of;

vibrating the articles in a drum containing the burnishing media,

the vibratory movement of said drum providing for the flow of media andmaterials in a circular orbit, subjecting a portion of said media as aseparate mass within said drum to a second rotating circular orbit ofsmaller diameter than said first orbit while said portion of media ismoving in said first orbit.

l l. The method in accordance with claim 10,

said portion, in said second orbit including metal articles beingconfined in a hollow member in response to said vibratory movement ofsAid first orbit.

12. The method in accordance with claim 11,

wherein said portion temporarily confined is discharged and otherportions of said articles become so temporarily confined.

13. A vibratory burnishing apparatus including;

a work drum for containing solid burnishing elements and a charge ofmetal articles to be burnished,

means mounting said drum for vibratory motion,

vibratory means for inducing vibratory motion to said drum,

the improvement comprising,

an apertured hollow member positioned freely within said drum to movewith said charge and burnishing elements in a vibratory manner,

said burnishing elements passing to and from said hollow member duringvibration of said drum.

14. The invention in accordance with claim 13,

said vibrating drum moving said charge, hollow member, and elements in acircular orbit and said hollow member rotating in a second smallerdiameter orbit while moving in said first orbit.

15. The invention in accordance with claim 14,

said drum having a semi-cylindrical wall and vertical side wallsconnected to said semi-cylindrical wall, said semi-cylindrical wallincluding a plurality of openings of smaller diameter than theindividual articles of said charge,

a closure member movably supported on said drum for opening and closingsaid openings,

said openings being larger than individual burnishing elements movingfrom said drum during vibratory motion and whereby said charge isretained in said drum.

16,. T e inventioni accordan e with c im 1, said rum having a bottom anside waif s, said axis of said cylindrical members being dispersednormal to said side walls, and said opening means including openings atopposite ends of said cylinder,

the wall of said said cylinder including apertures whereby burnishingmedia moves through said apertures toward said axis and along said axiswithin said cylindrical member.

17. In a burnishing apparatus,

a mobile burnishing chamber,

a revolving particle flowing or fluid burnishing media orbiting in apredetermined path in the chamber as a function of movement of thechamber, and

a perforated fluid-turbulence creating hollow member disposed with themedia in the chamber,

said member having port means communicating the interior of the hollowmember with the media attendant to orbiting of the hollow member withinthe predetermined path,

the port means including inlet and outlet means disseminating the mediain a convective manner within the chamber.

18. The method of polishing objects comprising the steps of:

within an orbital path within the movement of the burnishing mediaresulting in a turbulent dispersal of the media in and out of the memberwithin the drum, and 4. subjecting objects to be burnished To suchturbulent media.

1. A vibratory burnishing apparatus including; a work drum forcontaining burnishing media and a charge of metal materials to beburnished, means mounting said drum for vibratory motion, vibratorymeans for inducing vibratory motion to said drum, thereby imparting anorbital movement of the media and said charge, the improvementcomprising, a cylindrical member positioned within said drum, saidmember being positioned within said drum and said media and charge forrotation about its own axis, said cylinder including opening meanswhereby during vibration of said drum and rotation of said cylinder, inresponse to vibration of said media, said opening means provides for thepassage of said media to and from said cylindrical member.
 2. Theinvention in accordance with claim 1, said openings being dispersed atopposite ends of said cylindrical member and said cylindrical memberbeing positioned in said media for free movement therein.
 2. placing anaperture hollow turbulence creating member in the burnishing drum, 3.causing movement of the burnishing media within the drum whereby theapertured member moves within an orbital path within the movement of theburnishing media resulting in a turbulent dispersal of the media in andout of the member within the drum, and
 3. The invention in accordancewith claim 2, said media including burnishing balls,
 4. subjectingobjects to be burnished To such turbulent media.
 4. The invention inaccordance with claim 2, said cylindrical member moving in its own orbitin response to said orbital mOvement of said media.
 5. The invention inaccordance with claim 4, said cylindrical member having a cylindricalwall provided with a plurality of apertures permitting the free flow ofmedia therethrough.
 6. The invention in accordance with claim 5, saidapertures being of a size smaller than the individual components of saidcharge.
 7. The invention in accordance with claim 1, said drum having asemi-cylindrical bottom wall and vertical side walls connected thereto,said cylindrical member being despersed with its axis normal to saidwalls and being freely moveable within said drum in response to movementof said media.
 8. The invention in accordance with claim 7, said openingmeans including openings dispersed at opposite ends of said cylindricalmember and said openings being in relatively close adjacent relation tosaid vertical walls.
 9. The invention in accordance with claim 7, saidcylindrical member including a cylindrical wall having a plurality ofapertures through which said burnishing media passes.
 10. A method ofburnishing metal articles of relatively small size comprising the stepsof; vibrating the articles in a drum containing the burnishing media,the vibratory movement of said drum providing for the flow of media andmaterials in a circular orbit, subjecting a portion of said media as aseparate mass within said drum to a second rotating circular orbit ofsmaller diameter than said first orbit while said portion of media ismoving in said first orbit.
 11. The method in accordance with claim 10,said portion, in said second orbit including metal articles beingconfined in a hollow member in response to said vibratory movement ofsAid first orbit.
 12. The method in accordance with claim 11, whereinsaid portion temporarily confined is discharged and other portions ofsaid articles become so temporarily confined.
 13. A vibratory burnishingapparatus including; a work drum for containing solid burnishingelements and a charge of metal articles to be burnished, means mountingsaid drum for vibratory motion, vibratory means for inducing vibratorymotion to said drum, the imprOvement comprising, an apertured hollowmember positioned freely within said drum to move with said charge andburnishing elements in a vibratory manner, said burnishing elementspassing to and from said hollow member during vibration of said drum.14. The invention in accordance with claim 13, said vibrating drummoving said charge, hollow member, and eLements in a circular orbit andsaid hollow member rotating in a second smaller diameter orbit whilemoving in said first orbit.
 15. The invention in accordance with claim14, said drum having a semi-cylindrical wall and vertical side wallsconnected to said semi-cylindrical wall, said semi-cylindrical wallincluding a plurality of openings of smaller diameter than theindividual articles of said charge, a closure member movably supportedon said drum for opening and closing said openings, said openings beinglarger than individual burnishing elements moving from said drum duringvibratory motion and whereby said charge is retained in said drum. 16.The invention in accordance with claim 1, said drum having a bottom andside walls, said axis of said cylindrical members being dispersed normalto said side walls, and said opening means including openings atopposite ends of said cylinder, the wall of said said cylinder includingapertures whereby burnishing media moves through said apertures towardsaid axis and along said axis within said cylindrical member.
 17. In aburnishing apparatus, a mobile burnishing chamber, a revolving particleflowing or fluid burnishing media orbiting in a predetermined path inthe chamber as a function of movement of the chamber, and a perforatedfluid-turbulence creating hollow member disposed with the media in thechamber, said member having port means communicating the interior of thehollow member with the media attendant to orbiting of the hollow memberwithin the predetermined path, the port means including inlet and outletmeans disseminating the media in a convective manner within the chamber.18. The method of polishing objects comprising the steps of: